BILLET CONTINUOUS CASTING PROCESS Russian patent published in 2004 - IPC

FIELD: metallurgy, namely continuous casting of billets. SUBSTANCE: process comprises steps of determining pressure value in hydraulic cylinders of each pair of pinch rolls of drawing-breakdown stand at drawing out billet depending upon drawing out speed, temperature of billet surface, kind of cast steel according to next relations where K_p - dimensionless coefficient; S_L - extension value of liquid phase of billet, m; S_i - distance from metal meniscus in mold until i-rolls of breakdown stand, m; b - thickness of billet, m; h - width of billet, m; p₀ - pressure necessary for transporting billet without reduction, at; Δp_i - additional pressure in hydraulic cylinders of each pair of rolls necessary for reducing melt core of billet, at; p_i - pressure in hydraulic cylinders of each pair of rolls, at; T₀ - temperature of billet surface, C; k_i correction factor for each pair of rolls (1, 2, 3 and so on) depending upon operation pattern of drawing out stand; α₁, α₂ - coefficients depending upon steel kind, (α₁ = 50 - 150, α₂ = 4 - 10). Extension value of melt phase is determined according to given expression. EFFECT: enhanced microstructure of slab, lowered axial friability and axial liquation due to providing desired mode of reducing billet in solid-liquid state. 2 ex